Eco-home makes a £585,000 profit after just three years

A couple with eight children who built the greenest house in Britain have sold their home for a profit of £585,000.

Proving that nothing succeeds quite like ecofriendliness, Aaron and Raphaella Curtis spent £240,000 on their home and sold it three years later for £825,000.

"We've created an environmentally-friendly and fun living space on a brownfield site using local labour and materials," said Mr Curtis, 44, a construction project manager, "and we hope it will be an inspiration to others."

The five-bedroom, four-storey house - which won a national award for the greenest selfbuilt house - is on a small piece of scrubland near Lewes, East Sussex, which other developers had rejected as having no potential.

Worth just £60,000, the site is next to a partially demolished viaduct near a main railway line.

But by using a small plot, they realised they could build upwards without spending too much on land.

"It's like a Tardis inside," said Mr Curtis. "It's built on a small patch, but it cantilevers out so that there's plenty of space in the rooms above. We couldn't have afforded to buy a house like that."

The house incorporated the Victorian foundations of the crumbled viaduct into the design, which meant that only half the foundations had to be built from scratch.

It also features solar panels, state-of-the-art insulation and underfloor heating. The house was designed to have a minimal impact on the environment - but, as Mr Curtis admitted, being a family of 10 meant that much of their motivation was financial.

"We've been running normal-sized bills on an abnormal-sized family," he said.

He managed to keep building costs down by managing the project himself and using local craftsmen and materials. The exterior, for instance, is clad with sweet chestnut wood from five miles away.